1. Field of the Invention
The invention relates to the area of materials handling technology. It relates, in particular, to a spiral conveyor as well as to a deflecting device as claimed in the preamble of the corresponding independent claims.
2. Description of Related Art
Piece goods or bulk goods can be conveyed in conveying systems by way of belts or flush-grid chains. Spiral conveyors are used in order to overcome vertical distances, or to realize storage sections, buffer sections or delaying sections in the conveying system. However, large frictional losses occur in spiral conveyors, or in general in the case of the deflecting of pulled conveyor belts, in particular in resilient belts per se, curve-going flush-grid chains, link chains, plate chains and flat-top chains (referred to below collectively as conveying means). Consequently, it is deemed not to be possible to pull such conveyor belts or rather conveyor chains about an angle of deflection in excess of 180°. Consequently, drives of spiral conveyors are developed such that driving forces are introduced at several positions along the angle of deflection. To reduce frictional forces, it is known, for example from WO 99/35063, to arrange fixedly mounted rollers in a deflecting region.
WO 2009/036580A1 discloses a deflecting device as an independent structural unit which is installable in a conveying system as an independent structural unit for deflecting or for supporting in the case of a directional change of a conveying means. In this case, a roller body with several rollers rolls around a central body of the deflecting device. For use in the case of deflection around variously large angles, it is provided that the central body is assembled from several sector elements in modular construction, and a correspondingly shorter or longer roller body is then arranged around the central body. As an alternative to this, to realize different angles of deflection, the central body can be formed from a flexible material. When used in spiral conveyors, it is provided that the roller body ascends along a spiral lengthways of a conveyor belt and is subsequently returned again.
WO 2009/036581 A1 also describes a deflecting device, the form of the central body being adjustable in order to realize various radii of curvature or various angles of deflection.